1. Field of the Invention
The present invention relates generally to a barrel, and more particularly to an innovative one which is composed of an external metal cylinder and a plastic vessel positioned at the top of the structure.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98.
The conventional barrel products still have some disadvantages. For instance, the barrel structure of toilet brush assembly as shown in FIGS. 1 and 2, wherein the barrel 11 of a typical toilet brush assembly 10 is composed of a metal cylinder 111 and a metal bottom plate 112. A cup is placed into the barrel 11 to accommodate the sewage released from the toilet brush 13. However, the following shortcomings are observed during actual applications:
First, a metal bottom plate 112 must be assembled at the bottom of metal cylinder 111 of the barrel 11, leading to substantial increase of metal materials' cost. The metal cylinder 111 shall be assembled onto the metal bottom plate 112 through a special procedure (e.g. punching or rolling), thus increasing the manufacturing cost along with lowered manufacturing efficiency.
Second, if the inner space formed by the metal cylinder 111 and metal bottom plate 112 of the barrel 11 is used to accommodate the sewage released from the toilet brush 13, corrosion, fracture or damage will occur rapidly. Hence, a cup 12 is arranged into the barrel 11, leading to increase of material cost. Moreover, since a gap still exists between the cup 12 and metal cylinder 111, residual water on the wall of cup 12 and metal cylinder 111 will possibly bring about corrosion at the joint of the metal bottom plate 112 and metal cylinder 111.
Third, as the cup 12 of typical barrel 11 is used to accommodate the sewage released from the toilet brush 13, it is required to take out the cup 12 manually from the barrel 11 when it is intended to clean up the sewage, leading to inconvenience of operation and difficulty of cleaning because of limited inner space of the barrel 11.
Fourth, as illustrated in related U.S. Pat. No. 3,800,994, a convex ring flange is recessed onto the tubular body adjacent to the lower part of the curling portion, and the cylinder is inserted into the tubular body, such that the inner wall of the convex ring flange is clamped onto external wall of the cylinder. In such a case, an annular recessed space is formed between the convex ring flange and the cylinder, so dirt is accumulated and germs are bred to create trouble in routine cleaning.
Fifth, as illustrated in the related U.S. Pat. No. US2004/0262171A1, the bottom of the internal cylinder is extended to the lower opening of the external cylinder during the rolling process, the curling flange of the lower opening may contact frictionally with the bottom of the internal cylinder, leading to damage of the internal cylinder. Moreover, as the top and bottom of the internal cylinder are only abutted with the curling flange of the upper and lower openings of the external cylinder, the internal cylinder cannot be positioned stably when the curling flange of external cylinder is subject to roller forming. In such a case, the curling flange of the upper and lower openings must be rolled separately to form an abutting position for the internal cylinder, thus leading to lower manufacturing efficiency.
Thus, to overcome the aforementioned problems of the prior art, it would be an advancement if the art to provide an improved structure that can significantly improve the efficacy.
Therefore, the inventor has provided the present invention of practicability after deliberate design and evaluation based on years of experience in the production, development and design of related products.